Diff: ADS8568_ADC.cpp

Revision:

0:d59f808e1719

Child:

1:cedf75de6aec

Child:

2:52a40eb59b06

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/ADS8568_ADC.cpp	Tue Jul 16 14:22:31 2019 +0000
@@ -0,0 +1,94 @@
+/*------------------------------------------------------------------------------
+Library code file for interface to ADS8568 TI 16 bit 8 channel sampling ADC
+Date: 15/07/2018
+Author: AS7
+
+
+------------------------------------------------------------------------------*/
+
+#include "ADS8568_ADC.h"
+
+
+    
+ADS8568_ADC::ADS8568_ADC(PinName mosi, PinName miso, PinName sclk, PinName ncs,PinName reset, PinName convA, PinName convB, PinName convC, PinName convD)
+: bus(mosi, miso, sclk), adc_nselect(ncs), adc_reset(reset), converts(convA, convB, convC, convD)
+{
+    /*
+    bus = new SPI(mosi, miso, sclk);
+    adc_nselect = new DigitalOut(ncs);
+    adc_reset = new DigitalOut(reset);
+    converts = new BusOut(convA, convB, convC, convD);
+    */
+    
+    //constants are defined in protected and initialised here
+
+    channels_read = 0;
+    OSR = 1;
+    dummy = 0;
+    
+}
+
+void ADS8568_ADC::init()
+{
+    //set SPI serial to 2MHz, 16 bit data transfer, mode 2 (clock normally high, data preceeding clock cycle) 
+    bus.format(8,2);
+    bus.frequency(2000000);
+    bus.set_default_write_value(0x00);
+    adc_nselect = 1;
+    
+    //Reset ADC sequence
+    adc_reset = 1;
+    wait_ms(1);
+    adc_reset = 0;    
+}
+
+void ADS8568_ADC::start_conversion(int channels)
+{
+    //send convert signal to all channels
+    converts = channels;
+    wait_us(1);
+    converts = 0;
+    
+    //save which channels have been converted
+    channels_read = channels;
+}
+
+int ADS8568_ADC::read_channels()
+{
+
+    //SPI(like) data transfer
+    adc_nselect = 0;
+    bus.write(&dummy, 1, buffer, 16);
+    adc_nselect=1;
+    
+    //loop over bytes to add channel voltage values
+    for (int x=0; x<8; x++){
+            val_array[x] = buffer[2*x]<<8 | buffer[(2*x) + 1];
+            values [x] = values[x] + val_array[x]; 
+        }
+    
+            
+    return 0;
+}
+
+int ADS8568_ADC::read_channel_result(int channel)
+{
+    //make sure channel exists to prevent memory error
+    if(channel >= 0 && channel < 8)
+    {
+        //update channels_read to indicate which data has been converted but not read into application
+        channels_read = channels_read - (channels_read & channel);
+        
+        //return ADC channel value        
+        return values[channel];
+        }
+        
+    //if error return -1 
+    return -1;
+}
+
+int ADS8568_ADC::new_data_channels()
+{
+    //check which channels have been converted but not read yet
+    return(channels_read);
+}
\ No newline at end of file